I'm planning on installing Ikea shelves mounted on wall brackets (using the Antonius system). Until recently there were Antonius shelves 14 3/8 inches deep, but now they've disappeared, leaving only 11 inches deep shelves. There is a 14 3/8 deep shelf (a Broder shelf), but to attached to the wall mount I need brackets. There are only brackets for 11 inch shelves. The shelves are planned to store dry food stuff mostly (cans, pasta, rice, potatoes, etc.), so it might be quite heavy.
What is the harm in using shorter brackets with a deeper shelf? The only things I can think of are a reduced carrying capacity for the bracket and since the out edge of the shelf is not supported, it might be break. But how realistic is that the 3 3/8 edge will break from a static load? The deeper shelf is wood (as opposed to particle board for the Antonius shelves).